Optical Image Stabilization (OIS) is a hardware-based stabilization technology that physically compensates for camera motion by moving the lens elements or image sensor in response to detected vibration. Gyroscopic sensors measure camera movement and actuators shift the optical components in real time to keep the image steady on the sensor. OIS operates before the image is captured, preserving the full field of view and producing higher quality stabilization than purely digital methods, particularly for low-light footage.